1. Field of the Invention
The present invention relates generally to a film transporting device, and more particularly to a film transporting device applied to a camera, a film scanner, a film viewer, and the like.
2. Description of the Related Art
A camera is proposed which uses photographic film coated with a magnetic recording layer, and writes the date and time of photographing, the photographing information, etc. by a magnetic head, or reads out the information from the photographic film while the photographic film is fed during photographing (Japanese Patent Provisional Publication Nos. 4-60531 and 4-86639). After the photographic film is developed, the information recorded in the magnetic recording layer is used when film images are picked up by an image sensor and are displayed on a TV monitor, or when the film images are printed on printing paper.
In order to correctly write the information in the magnetic recording layer or read out the information, the photographic film must be accurately transported toward the magnetic head. The photographic film is fed in such a manner that both edges in the longitudinal direction are guided by guide pins. However, because the guide pins are arranged at intervals wider than the width of the photographic film, the guide pins alone cannot prevent the photographic film from being displaced during feeding. Thus, the magnetic recording layer does not accurately contact the magnetic head, and the information cannot be correctly written.
To eliminate the above-mentioned disadvantages, the camera in Japanese Patent Provisional Publication No. 4-60531 prevents the displacement between the magnetic recording layer and the magnetic head by fixing the magnetic head to a continuous guide member and pressing the guide member against one edge of the photographic film by a spring during feeding.
In the camera of Japanese Patent Provisional Publication No. 4-866939, the magnetic head is fixed to a film pressure plate, which is moved by the force of a spring. The guide member formed at the film pressure plate is thereby pressed against one edge of the photographic film which is being fed, so that the displacement between the magnetic recording layer and the magnetic head can be prevented.
A film image input device has been recently proposed which picks up images on a developed continuous photographic film by an image sensor such as a charge coupled device (CCD), and displays the images on a TV monitor.
FIG. 14 shows one example of a conventional film image input device. As shown in FIG. 14, the developed photographic film 2 is pulled out from a film cartridge 1, and the photographic film 2 which curves in the direction of its width is straightened by curved guide plates 3. Then, the light source 4 illuminates film images on the straightened photographic film, and a line sensor 5 picks up the transmitted images through a taking lens. The photographic film 2 passes through a scanning area of the line sensor 5, and it is fed in such a manner that one edge 2A is pressed against a pair of guide pins 6 by a pressing means (not shown) provided at the rear of the pair of guide pins 6. Information is written in or read from a magnetic recording layer 8 on the photographic film 2 by magnetic heads 7, and then the photographic film 2 is wound up by a windup reel 9. The inventors of this application have disclosed the above-mentioned guide plate 3 in Japanese Patent Provisional Publication No. 7-298135, and proposed the above-mentioned pressing means in Japanese Patent Application No. 6-313266.
A displacement prevention mechanism disclosed in Japanese Patent Provisional Publication Nos. 4-60531 and 4-86639 moves the magnetic head via the guide member and a film pressure plate. Thus, this displacement prevention mechanism has a disadvantage in that the structure thereof is complicated and many parts are required. The film image input device in FIG. 14 has a disadvantage because the film, which must be kept flat by a guide plate 3 in a direction in which a line sensor reads film images, curves due to the difference of the mounting position of the film cartridge 1, and the warped images are displayed on the TV monitor.
Such disadvantages can be solved if the pressing means is not provided, and therefore the photographic film 2 against the guide pins 6. In this case, however, the photographic film 2 is not pressed and the magnetic heads 7 are displaced, and the film images cannot be read steadily, or the magnetic information cannot be read or written steadily.